The invention relates to improvements in methods of and in apparatus for building and manipulating plural streams of fibrous material, such as tobacco. More particularly, the invention relates to improvements in methods of and in apparatus for building, guiding and trimming two or more streams each of which can be converted into a rod-like filler, e.g., into a filler of the type suitable for draping into a web of cigarette paper or other wrapping material to form with the web a continuous rod which is ready to be subdivided into rod-like sections (e.g., plain cigarettes) of unit length or multiple unit length.
It is known to deliver fibrous material (such as fragments of tobacco leaf laminae, tobacco ribs, reconstituted tobacco and/or substitute tobacco) to a stream building zone wherein the delivered fibrous material is converted into a plurality of discrete streams each of which is advanced by a discrete conveyor and each of which normally contains a surplus of fibrous material. The surplus must be removed by suitable trimming or equalizing devices in order to convert each stream into a rod-like filler which is ready for condensing, wrapping and subdivision into discrete rod-like sections of desired length. The machine is equipped with means for removing the surplus from the discrete streams so as to convert each stream into a rod-like filler which is ready for condensing and wrapping prior to advancing to a cutoff wherein the wrapped filler is subdivided into a file of discrete rod-shaped articles. Heretofore known machines of the just outlined character exhibit the drawback that the removal of surplus from the stream necessitates the utilization of complex, sensitive and expensive trimming or equalizing devices. This is attributable, at least in part, to the fact that all heretofore known machines for simultaneous building and processing of two or more streams of fibrous material are equipped with conveyors which advance the streams along closely adjacent parallel paths.